Counter-weights for a crankshaft

ABSTRACT

A COUNTER-WEIGHT FOR CRANKSHAFT IS WHICH THE PART OF THE COUNTER-WEIGHT THAT NORMALLY IS IMMERSED IN THE LUBRICANT SUMP IS CONSTRUCTED AS A DISPLACEMENT BODY WITH LOW FLOW RESISTANCE TO LIQUID.

United StateS Patent O 3559504 COUNTER-WEIGI-ITS FOR A CRANKSHAFT Herbert Deutschmann, Stuttgart-Bad Cannstatt, Jrgen Wahnschalfe, Stuttgart-Stammheim, and Wolfgang Rudert, Grunbach, Kreis Waiblingen, Germany, assignol's to Daimler-Benz Aktiengesellschaft, Stuttgart- Unterturkheim, Germany Filed June 14, 1968, Ser. N0. 737,233 Claims priority, application Germany, June 15, 1967, P 15 75 426.4 Int. Cl. Fl6f 15/00 U.S. Cl. 74603 6 Claims ABSTRACT OF THE DISCLOSURE A counter-weight for crankshafts in which the part of the counter-weight that normally is immersed in the lubricant sump is constructed as a displacement body with 10W flow resistance to liquid.

The present invention relates to a counter-weight for a crankshaft and aims at reducing the harmful splash WOIk in the cran=kcase bottom part. F01 this purpose, the counter-weight plunging into the lubricant sump is constructed according to the present invention as 10W- resistance displacement body.

In a first embodiment of the present invention, the displacement body may have the form of a ships bow.

In a second advantageous type of construction of the displacement body according to the present invention, the displacement body may have one or several guide surfaces along which the lubricant particles are displaced in the direction of the sump bottom. The guide surfaces are appropriately curved and have at least two different curvatures whereby a larger curvature follows a smaller curvature in the direction of rotation of the counterweight.

Accordingly, it is an object cf the present invention to provide counter-weights for crankshafts which obviate the shortcomings and drawbacks encountered in the prior art by simple means.

Another object of the present invention resides in counter-weights for crankshafts of internal combustion engines in-which the harmful splash work in the crankcase bottom part is reduced.

A further object of the present invention resides in counter-weights for crankshafts of the internal combustion engines which are so constructed and arranged as to constitute displacement bodies that efiectively provide a 10W resistance to the liquid flow and therewith to immersion into the sump.

Still a further object of the present invention resides in a counterweight for a crankshaft which achieves all of the aforernentioned aims and objects by structurally simple parts that can be manufactured with relatively little expense.

These and further objects, features, and advantages of the present invention will become more obvious from the following description when taken in connection With the accompanying drawing which shows, for purposes cf illustration only, two embodiments of counter-weights in accordance With the present invention, and wherein:

FIG. 1 is an elevational view f a first embodiment of a counter-weight in accordance with the present in- Patented Feb. 2, 1971 'ice vention provided with a displacement body similar to a ships bow;

FIG. 2 is a plan view of the counter-weight of FIG. 1 taken in the direction of arrow II; and

FIG. 3 is an elevational view cf a second embodiment of a counter-weight in accordance with the present invention whose outer displacernent body has a doubly curved guide surface at its circumference.

Referring now to the drawing Wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIGS. 1 and 2, the counter-weight illustrated in these two figures has the usual form of a segment of a circular arc With an aperture 10 into which engages a securing part of the crankshaft in the assembled condition For the purpose of securing the counter-weight at the crankshaft, the counterweight is provided with two through-bores 11 and 12 for threaded bolts (not shown). The two ends generally designated by reference numerals 13 and 14 of the counterweight, disposed in the circumferential direction, have as viewed in the direction of arrow I-Ithe wedge-shape 15 of a ships bow. The inclined arrangernent of the surfaces 15a and 15b reduces the impact eifect and the flow resistance of the cheek part 16 during the immersion into the lubricant sump.

The counter-weight in FIG. 3 also has a conventional form of a segment of a circular arc with an aperture 30 for its securing at the crankshaft. In the sarne manner, through-bores 31 and 32 for the securing bolts are also provided in this counter-weight.

The outer cheek part 36 is defined at the circumference thereof by cylindrical outer su1faces 37, 38a and 38b.

Whereas the central outer surface 37 is curved relatively slightly by reason of a larger radius of curvature R, the symmetrical outer surfaces 38a and 38b have a relatively strong curvature by reason of a smaller radius of curvature r. As a result of this construction cf the outer cheek part 36, the lubricant particles impingin'g within the area A against the counter-weight are dis placed in the direction of arrow B in which the bottom of the lubricant sump must be thought of as being located.

Also, in this manner, the impact effect and flow resistance of the outer cheek part 36 is reduced. Additionally, it is avoided thereby that the lubricant particles are centrifuged or thrown upwardly into the interior space of the crankcase bottom part by the outer surfaces of the counter-weight.

While we have shown and described several embodiments in accordance With the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art, and We therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications 'as are encompassed by the scope of the appended claims.

We claim:

1. A counter-weight for a crankshaft having a counterweight part constituting a displacement body being adapted for plunging into a lubricant sump, characterized in that said displacement body has means for lowering the resistance during the plunging thereof into the lubricant sump.

2. A counler-weight according to claim 1, wherein said means includes the displacement body having substantially the shape of a ships bow in the circumferential direction of said counter-weight.

3. A counter-weight according to claim 1, wherein said means includes the displacement body having at least one guide surface means dipping into the sump for displacing the lubricant particles in the direction of the sump bottom.

4. A counter-weight according to claim .3. wherein several guide surfaces means are provided at the displacement body.

5. A counter-weight according to claim 4, wherein each guide surface means has at least two different radii 0f curvature, and wherein a surface means With a larger radius of curvature follows a surface means with a smal1er radius of curvature in the direction of rotation of the counter-weight.

6. A counter-weight according to claim 3, wherein each guide surface means has at least two different radii of curvature, and wherein a surface means with a larger radius of curvature follows a surface means with a smaller radius of curvature in the direction of rotation of the counter-weight.

References Cited UNITED STATES PATENTS 14.292 4/1917 Fekete 7 6O3 1,645,718 10/1927 Oldson 74603 1,649541 11/1927 Oldson 74-603 1661341 3/1928 Oldson 74603 1803317 5/1931 Brown 74-603 1.817.389 8/1931 Meyer 74-603 2,838941 6/1958 Tur1ay 74603X OTHER REFERENCES 749,164 5/1956 Great Britain 74603 FRED C. MATTERN, JR. Primary Examiner 20 F. D. SHOEMAKER, Assistant Examiner 

